Power supply unit for aerosol inhaler

ABSTRACT

A power supply unit for an aerosol inhaler includes: a power supply able to discharge power to a load for generating an aerosol from an aerosol source; a first control device and a second control device which are configured to control at least one of charging and discharging of the power supply; a circuit board on which the first control device and the second control device are provided; a first capacitor which is provided on an input side of the first control device so as to be connected in parallel with the first control device; and a second capacitor which is provided on an input side of the second control device so as to be connected in parallel with the second control device, wherein a capacity of the first capacitor is different from a capacity of the second capacitor.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromprior U.S. provisional application No. 62/793,551, filed on Jan. 17,2019 and prior Japanese patent application No. 2019-035990, filed onFeb. 28, 2019, the entire contents of which are incorporated herein byreference.

TECHNICAL FIELD

The present invention relates to a power supply unit for an aerosolinhaler.

BACKGROUND ART

In Patent Literature 1, a non-combustion type flavor inhaler includingan atomizing unit having a load for atomizing an aerosol source withoutcombustion, and a power supply unit including a power supply forsupplying power to the load is disclosed. In general, a power supplyunit includes not only a power supply but also a connector that can beelectrically connected to an external power supply, and a control device(a control unit, a charger, and so on) that is configured to control atleast one of charging and discharging of the power supply or that isconfigured to be able to convert power which is input from the connectorinto charging power for the power supply.

For example, in Patent Literature 2, a power supply unit having aplurality of capacitors provided on the downstream side from a chargerso as to be connected in parallel with the charger is disclosed. InPatent Literature 3, a power supply unit having a capacitor providedbetween a connector and a charger so as to be connected in parallel withthe charger in order to stabilize voltage to be input to the charger isdisclosed.

[Patent Literature 1] WO 2018/163261 A1

[Patent Literature 2] CN 206865186 U

[Patent Literature 3] US 2015/0173124 A1

However, in a power supply unit having a plurality of control devices onthe same circuit board, it is difficult to appropriately protect theplurality of control devices, and the areas on the circuit board whichcapacitors and so on occupy increase. Therefore, the size of the powersupply unit may increase.

An object of the present invention is to provide a power supply unit foran aerosol inhaler capable of reducing the areas on a circuit boardwhich capacitors occupy while appropriately protecting a plurality ofcontrol devices.

SUMMARY OF INVENTION

According to an aspect of the invention, there is provided a powersupply unit for an aerosol inhaler, the power supply unit comprising: apower supply able to discharge power to a load for generating an aerosolfrom an aerosol source; a first control device and a second controldevice which are configured to control at least one of charging anddischarging of the power supply; a circuit board on which the firstcontrol device and the second control device are provided; a firstcapacitor which is provided on an input side of the first control deviceso as to be connected in parallel with the first control device; and asecond capacitor which is provided on an input side of the secondcontrol device so as to be connected in parallel with the second controldevice, wherein a capacity of the first capacitor is different from acapacity of the second capacitor.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of an aerosol inhaler equipped with a powersupply unit of an embodiment of the present invention.

FIG. 2 is another perspective view of the aerosol inhaler of FIG. 1.

FIG. 3 is a cross-sectional view of the aerosol inhaler of FIG. 1.

FIG. 4 is a perspective view of the power supply unit in the aerosolinhaler of FIG. 1.

FIG. 5 is an exploded perspective view illustrating the internalconfiguration of the power supply unit in the aerosol inhaler of FIG. 1.

FIG. 6 is a block diagram illustrating the main part configuration ofthe power supply unit in the aerosol inhaler of FIG. 1.

FIG. 7 is a schematic diagram illustrating the circuit configuration ofthe power supply unit in the aerosol inhaler of FIG. 1.

FIG. 8A is a circuit diagram including a zener diode.

FIG. 8B is an explanatory view illustrating the breakdown voltage of thezener diode.

FIG. 8C is an explanatory view illustrating pulsation of input voltagefor a charger.

FIG. 8D is an explanatory view illustrating voltage stabilizationattributable to the zener diode.

FIG. 9 is an explanatory view illustrating a range of zener diodessuitable as a second zener diode (or a first zener diode) of the powersupply unit in the aerosol inhaler of FIG. 1.

FIG. 10 is an explanatory view illustrating the operation principle of asmoothing capacitor of the power supply unit in the aerosol inhaler ofFIG. 1.

FIG. 11 is a circuit diagram including a low pass filter.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a power supply unit for an aerosol inhaler according to anembodiment of the present invention will be described. First of all, anaerosol inhaler equipped with the power supply unit will be describedwith reference to FIG. 1 to FIG. 3.

(Aerosol Inhaler)

An aerosol inhaler 1 is a device for inhaling a flavor withoutcombustion, and has a rod shape extending along a certain direction(hereinafter, referred to as the longitudinal direction A). The aerosolinhaler 1 includes a power supply unit 10, a first cartridge 20, and asecond cartridge 30 which are arranged in the order along thelongitudinal direction A.

The first cartridge 20 can be attached to and detached from the powersupply unit 10, and the second cartridge 30 can be attached to anddetached from the first cartridge 20. In other words, the firstcartridge 20 and the second cartridge 30 can be individually replaced.

(Power Supply Unit)

The power supply unit 10 of the present embodiment includes a powersupply 12, a charger 13, a control unit 50, various sensors, and so oninside a cylindrical power supply unit case 11, as shown in FIG. 3 toFIG. 6. The power supply 12 is a chargeable secondary battery, anelectric double-layer capacitor, or the like, and is preferably alithium-ion battery.

On a top part 11 a of the power supply unit case 11 positioned on oneend side in the longitudinal direction A (the first cartridge (20)side), a discharging terminal 41 is provided.

The discharging terminal 41 is provided so as to protrude from the topsurface of the top part 11 a toward the first cartridge 20, and isconfigured to be able to be electrically connected to a load 21 of thefirst cartridge 20.

Further, on a part of the top surface of the top part 11 a in thevicinity of the discharging terminal 41, an air supply part 42 forsupplying air to the load 21 of the first cartridge 20 is provided.

On a bottom part 11 b of the power supply unit case 11 positioned on theother end side in the longitudinal direction (the opposite side to thefirst cartridge 20), a charging terminal 43 able to be electricallyconnected to an external power supply 60 (see FIG. 7) capable ofcharging the power supply 12 is provided. The charging terminal 43 isprovided on the side surface of the bottom part 11 b, such that at leastone of USB terminals, micro USB terminals, and Lightning (registered asa trade mark) terminals can be connected thereto.

However, the charging terminal 43 may be a power receiving part able toreceive power from the external power supply 60 in a non-contact manner.In this case, the charging terminal 43 (the power receiving part) may becomposed of a power receiving coil. The wireless power transfer systemmay be an electromagnetic induction type, or may be a magnetic resonancetype. Also, the charging terminal 43 may be a power receiving part ableto receive power from the external power supply 60 without any contactpoint. As another example, the charging terminal 43 may be configuredsuch that at least one of USB terminals, micro USB terminals, andLightning (registered as a trade mark) terminals can be connectedthereto and the above-mentioned power receiving part is includedtherein.

In other words, the discharging terminal 41 and the charging terminal 43are separately configured, and are disposed apart from each other in thelongitudinal direction A. Therefore, the power supply unit 10 isconfigured such that in a state where discharging of the power supply 12through the discharging terminal 41 is possible, it is possible toelectrically connect the external power supply 60 to the chargingterminal 43. Also, in the power supply unit 10, in a state where thecharging terminal 43 and the external power supply 60 are electricallyconnected, if an aerosol generation request is detected, it isprohibited to perform charging and discharging of the power supply 12 atthe same time.

Also, on the side surface of the top part 11 a of the power supply unitcase 11, an operation unit 14 which the user can operate is provided soas to face the opposite side to the charging terminal 43. Morespecifically, the operation unit 14 and the charging terminal 43 aresymmetric with respect to the point of intersection of a straight lineconnecting the operation unit 14 and the charging terminal 43 and thecenter line L of the power supply unit 10 in the longitudinal directionA. The operation unit 14 is composed of a button type switch, a touchpanel, or the like, and is used to activate and shut off the controlunit 50 and various sensors and perform other operations according tothe intention of a user to use. In the vicinity of the operation unit14, the control unit 50 and an inhalation sensor 15 for detecting puffactions are provided.

The charger 13 controls charging power to be input from the chargingterminal 43 to the power supply 12. The charger 13 is configured with acharging IC including a converter for converting direct current, whichis applied from an inverter 61 or the like provided for convertingalternating current into direct current on a charging cable which isconnected to the charging terminal 43, into direct current having adifferent magnitude, a voltmeter, an ammeter, a processor, and so on.

The control unit 50 is connected to the charger 13, the operation unit14, various sensor devices such as the inhalation sensor 15 fordetecting puff (inhalation) actions, a voltage sensor 16 for measuringthe voltage of the power supply 12, and so on, and a memory 18 forstoring the number of puff actions, the time for which power has beenapplied to the load 21, and so on, as shown in FIG. 6, and performs avariety of control on the aerosol inhaler 1. The inhalation sensor 15may be compose of a capacitor microphone, a pressure sensor, or thelike. The control unit 50 is specifically a processor (a microcontroller unit (MCU)). The structure of this processor is morespecifically an electric circuit configured by combining circuitelements such as semiconductor elements and so on. The details of thecontrol unit 50 will be described below.

Also, in the power supply unit case 11, an air intake (not shown in thedrawings) for taking in air is formed. The air intake may be formedaround the operation unit 14, or may be formed around the chargingterminal 43.

(First Cartridge)

As shown in FIG. 3, the first cartridge 20 includes a reservoir 23 forstoring an aerosol source 22, the electric load 21 for atomizing theaerosol source 22, a wick 24 for drawing the aerosol source from thereservoir 23 toward the load 21, an aerosol channel 25 for an aerosolgenerated by atomizing the aerosol source 22 to flow toward the secondcartridge 30, and an end cap 26 for storing a part of the secondcartridge 30, inside a cylindrical cartridge case 27.

The reservoir 23 is formed so as to surround the aerosol channel 25, andholds the aerosol source 22. In the reservoir 23, a porous member suchas a resin web or cotton may be stored, and the porous member may beimpregnated with the aerosol source 22. The aerosol source 22 includes aliquid such as glycerin, propylene glycol, or water.

The wick 24 is a liquid holding member for drawing the aerosol source 22from the reservoir 23 toward the load 21 using capillarity, and isconfigured with, for example, glass fiber, a porous ceramic, or thelike.

The load 21 atomizes the aerosol source 22, without combustion, by powerwhich is supplied from the power supply 12 through the dischargingterminal 41. The load 21 is configured with a heating wire wound with apredetermined pitch (a coil). However, the load 21 needs only to be anelement capable of atomizing the aerosol source 22, thereby generatingan aerosol, and is, for example, a heat generating element or anultrasonic wave generator. Examples of the heat generating elementinclude a heating resistor, a ceramic heater, an induction heating typeheater, and so on.

The aerosol channel 25 is provided on the downstream side of the load 21on the center line L of the power supply unit 10.

The end cap 26 includes a cartridge storage part 26 a for storing a partof the second cartridge 30, and a connecting passage 26 b for connectingthe aerosol channel 25 and the cartridge storage part 26 a.

(Second Cartridge)

The second cartridge 30 holds a flavor source 31. An end part of thesecond cartridge 30 on the first cartridge (20) side is stored in thecartridge storage part 26 a provided in the end cap 26 of the firstcartridge 20, so as to be able to be removed. Another end part of thesecond cartridge 30 on the opposite side to the first cartridge (20)side is configured as an inhalation port 32 for the user. However, theinhalation port 32 does not necessarily need to be configured integrallywith the second cartridge 30 so as not to be separable from the secondcartridge, and may be configured to be able to be attached to anddetached from the second cartridge 30. If the inhalation port 32 isconfigured separately from the power supply unit 10 and the firstcartridge 20 as described above, it is possible to keep the inhalationport 32 sanitary.

The second cartridge 30 adds a flavor to the aerosol generated byatomizing the aerosol source 22 by the load 21, by passing the aerosolthrough the flavor source 31. As a raw material piece which constitutesthe flavor source, a compact made by forming shredded tobacco or atobacco raw material into a grain shape can be used. The flavor source31 may be configured with plants (such as mint, herbal medicines, andherbs) other than tobacco. To the flavor source 31, a flavoring agentsuch as menthol may be added.

The aerosol inhaler 1 of the present embodiment can generate an aerosolcontaining the flavor by the aerosol source 22, the flavor source 31,and the load 21. In other words, the aerosol source 22 and the flavorsource 31 can be referred to as an aerosol generation source forgenerating an aerosol.

The configuration of the aerosol generation source which can be used inthe aerosol inhaler 1 is not limited to the configuration in which theaerosol source 22 and the flavor source 31 are configured separately,and may be a configuration in which the aerosol source 22 and the flavorsource 31 are formed integrally, a configuration in which the flavorsource 31 is omitted and the aerosol source 22 contains a substancewhich can be contained in the flavor source 31, a configuration in whichthe aerosol source 22 contains a medical substance or the like insteadof the flavor source 31, or the like.

In the aerosol inhaler 1 configured as described above, as shown by anarrow B in FIG. 3, air entering from the intake (not shown in thedrawings) formed in the power supply unit case 11 passes through the airsupply part 42, and passes near the load 21 of the first cartridge 20.The load 21 atomizes the aerosol source 22 drawn from the reservoir 23by the wick 24. The aerosol generated by atomizing flows through theaerosol channel 25 together with the air entering from the intake, andis supplied to the second cartridge 30 through the connecting passage 26b. The aerosol supplied to the second cartridge 30 passes through theflavor source 31, whereby the flavor is added, and is supplied to theinhalation port 32.

Also, in the aerosol inhaler 1, the notifying unit 45 for notifying avariety of information is provided (see FIG. 6). The notifying unit 45may be configured with a light emitting element, or may be configuredwith a vibrating element, or may be configured with a sound outputelement. Alternatively, the notifying unit 45 may be a combination oftwo or more elements of light emitting elements, vibrating elements, andsound output elements. The notifying unit 45 may be provided in any oneof the power supply unit 10, the first cartridge 20, and the secondcartridge 30; however, it is preferable that the notifying unit beprovided in the power supply unit 10. For example, the area around theoperation unit 14 is configured to have translucency to permit lightwhich is emitted by light emitting elements such as LEDs to passthrough.

(Electric Circuit)

Now, the electric circuit of the power supply unit 10 will be describedwith reference to FIG. 7.

The power supply unit 10 includes the power supply 12, a positiveelectrode side discharging terminal 41 a and a negative electrode sidedischarging terminal 41 b which constitute the discharging terminal 41,a positive electrode side charging terminal 43 a and a negativeelectrode side charging terminal 43 b which constitute the chargingterminal 43, the control unit 50 which is connected between the positiveelectrode side of the power supply 12 and the positive electrode sidedischarging terminal 41 a and between the negative electrode side of thepower supply 12 and the negative electrode side discharging terminal 41b, the charger 13 which is disposed on the power transmission pathbetween the charging terminal 43 and the power supply 12, a switch 19which is disposed on the power transmission path between the powersupply 12 and the discharging terminal 41, and a first zener diode 71, asecond zener diode 72, a resistor 73, a first capacitor 74, and a secondcapacitor 75 to be described below. The switch 19 is configured with,for example, a MOSFET, and is turned on and off according to gatevoltage which is adjusted by the control unit 50.

(Control Unit)

As shown in FIG. 6, the control unit 50 includes an aerosol generationrequest detecting unit 51, an operation detecting unit 52, a powercontrol unit 53, and a notification control unit 54.

The aerosol generation request detecting unit 51 detects a request foraerosol generation based on the output result of the inhalation sensor15. The inhalation sensor 15 is configured to output the value of avariation in the pressure in the power supply unit 10 caused byinhalation of the user through the inhalation port 32. The inhalationsensor 15 is, for example, a pressure sensor for outputting an outputvalue (for example, a voltage value or a current value) according to theatmospheric pressure which varies according to the flow rate of airwhich is sucked from the intake (not shown in the drawings) toward theinhalation port 32 (i.e. a puff action of the user).

The operation detecting unit 52 detects operations which are performedon the operation unit 14 by the user.

The notification control unit 54 controls the notifying unit 45 suchthat the notifying unit notifies a variety of information. For example,the notification control unit 54 controls the notifying unit 45 inresponse to detection of the timing to replace the second cartridge 30,such that the notifying unit notifies the timing to replace the secondcartridge 30. The notification control unit 54 notifies the timing toreplace the second cartridge 30, based on the number of puff actions orthe cumulative time for which power has been supplied to the load 21,stored in the memory 18. The notification control unit 54 is not limitedto notification of the timing to replace the second cartridge 30, andmay notify the timing to replace the first cartridge 20, the timing toreplace the power supply 12, the timing to charge the power supply 12,and so on.

The power control unit 53 controls discharging of the power supply 12through the discharging terminal 41 by switching on and off the switch19, if the aerosol generation request detecting unit 51 detects therequest for aerosol generation.

The power control unit 53 performs control such that the amount ofaerosol which is generated by atomizing the aerosol source by the load21 falls in a desired range, i.e. such that the amount of power which issupplied from the power supply 12 to the load 21 falls in apredetermined range. Specifically, the power control unit 53 controlsswitching on and off of the switch 19 by, for example, PWM (Pulse WidthModulation) control. Alternatively, the power control unit 53 maycontrol switching on and off of the switch 19 by PFM (Pulse FrequencyModulation) control.

After supply of power to the load 21 starts, if a predetermined periodpasses, the power control unit 53 stops supply of power from the powersupply 12 to the load 21. In other words, even while the user isactually performing a puff action, if the puff period exceeds a certainperiod, the power control unit 53 stops supply of power from the powersupply 12 to the load 21. The certain period is determined to suppressvariation in user's puff period. The power control unit 53 controls theon/off duty ratio of the switch 19 for one puff action, according to theamount of power stored in the power supply 12. For example, the powercontrol unit 53 controls the interval between ON periods in which poweris supplied from the power supply 12 to the load 21 (the pulse interval)and controls the length of each ON period in which power is suppliedfrom the power supply 12 to the load 21 (the pulse width).

Also, the power control unit 53 detects an electric connection betweenthe charging terminal 43 and the external power supply 60, and controlscharging of the power supply 12 through the charger 13.

(Board Configuration)

As shown in FIG. 5 and FIG. 7, the power supply unit 10 includes a firstcircuit board 76 on which the charging terminal 43, the second zenerdiode 72, and the resistor 73 are provided, a second circuit board 77 onwhich the control unit 50, the charger 13, the switch 19, the firstzener diode 71, the first capacitor 74, the second capacitor 75, theoperation unit 14, and the inhalation sensor 15 are provided, and aconductive member 78 which electrically connects the first circuit board76 and the second circuit board 77. The conductive member 78 is a partof a conductor which electrically connects the charging terminal 43 andthe charger 13, and the conductive member 78 of the present embodimentis configured with a flexible circuit board; however, it may beconfigured with a conductive wire.

As shown in FIG. 5, the first circuit board 76 and the second circuitboard 77 are disposed apart from each other. Specifically, on one endside of the power supply 12 in the longitudinal direction (thelongitudinal direction A), the first circuit board 76 is provided, andon the other end side of the power supply 12 in the longitudinaldirection (the longitudinal direction A), the second circuit board 77 isprovided, and the first circuit board 76 and the second circuit board 77are electrically connected through the conductive member 78 extending inthe longitudinal direction of the power supply 12 along the periphery ofthe power supply 12. Alternatively, on one end side of the power supply12 in the width direction (the direction perpendicular to thelongitudinal direction A), the first circuit board 76 may be provided,and on the other end side of the power supply 12 in the width direction,the second circuit board 77 may be provided.

(First Zener Diode)

The first zener diode 71 is provided between the charging terminal 43and the charger 13 so as to be connected in parallel with the charger13. According to this first zener diode 71, it is possible to stabilizevoltage to be input to the charger 13. In other words, as shown in FIG.8B, the zener diode has a small breakdown voltage V_(BD) at whichcurrent flowing in the backward direction suddenly increases (thebackward current prevention action which the diode originally has islost). Therefore, the zener diode is likely to break down. In this case,as shown in FIG. 8A, the voltage between both ends of the zener diode isfixed at V_(BD), and the relation of Vout (Output Voltage)=V_(BD) isestablished. Therefore, even though input voltage Vin pulsates as shownin FIG. 8C, stable output voltage Vout without pulsation as shown inFIG. 8D is obtained.

Also, in a circuit shown in FIG. 8A, it should be noted that in the casewhere voltage which is applied between both ends of the zener diode islower than the breakdown voltage, the output voltage Vout becomes equalto the input voltage Vin.

The first zener diode 71 is connected closer to the input terminal ofthe charger 13 than to the output terminal of the charging terminal 43.According to this first zener diode 71, in addition to stabilization ofvoltage which is supplied from the charging terminal 43, it is possibleto eliminate pulsation of the voltage attributable to an L (reactance)component ineluctably existing between the charging terminal 43 and thecharger 13, thereby appropriately protecting the charger 13. Thisineluctably existing L component is caused by, for example, theconductive member 78 and the resistor 73.

As described above, the first zener diode 71 is provided on the secondcircuit board 77. In other words, since the charging terminal 43 and thecharger 13 are provided on the different circuit boards 76 and 77, thedegree of freedom in laying out individual components in the powersupply unit 10 is high. Also, since the first zener diode 71 is providedon the second circuit board 77 where the charger 13 is provided, it ispossible to dispose the first zener diode 71 close to the charger 13.However, the first zener diode 71 may be provided on the downstream sideof the conductive member 78 in the flow direction of power which isinput from the charging terminal 43, not on the second circuit board 77.Even in this case, it is possible to dispose the first zener diode 71close to the charger 13. If the first zener diode is disposed close tothe charger 13 as described above, it is possible to input voltagestabilized by eliminating pulsation by the first zener diode 71, to thecharger 13.

The first zener diode 71 is directly connected to a bus 79 whichelectrically connects the charging terminal 43 and the charger 13. Inother words, since the first zener diode 71 is connected without aswitch such as a transistor interposed therebetween, it is possible toavoid an increase in the size of the structure around the first zenerdiode 71. Furthermore, in the aerosol inhaler 1, since large current andhigh voltage are not handled, even if the first zener diode 71 is notconnected to a switch such as a transistor, it is possible tosufficiently stabilize voltage.

(Second Zener Diode)

The second zener diode 72 is provided between the charging terminal 43and the first zener diode 71 so as to be connected in parallel with thefirst zener diode 71. According to this configuration, whilefluctuations in voltage which is input from the external power supplyare eliminated by the second zener diode 72, pulsation of the voltageattributable to the L component ineluctably existing between thecharging terminal 43 and the charger 13 is eliminated by the first zenerdiode 71. Therefore, it is possible to more surely protect the charger13. Also, since different roles are assigned to the first zener diode 71and the second zener diode 72, it is possible to restrain the sizes andcosts of the zener diodes from increasing. Furthermore, it is possibleto restrain heat generation from being concentrated in one zener diode.Moreover, since the L component responds to change in voltage or currentover time, fluctuations in voltage which is input from the externalpower supply are eliminated by the second zener diode 72 disposedimmediately before the place where the L component occurs. Therefore, itis possible to apply stabler voltage to the charger 13.

As described above, the second zener diode 72 is provided on the firstcircuit board 76, and the first zener diode 71 is provided on the secondcircuit board 77 apart from the first circuit board 76. However, thesecond zener diode 72 may be provided on the upstream side of theconductive member 78 in the flow direction of power which is input fromthe charging terminal 43, and the first zener diode 71 may be providedon the downstream side of the conductive member 78 in the flow directionof power which is input from the charging terminal 43.

The first zener diode 71 and the second zener diode 72 are configuredwith identical components. In this case, component management becomeseasy, and it is possible to reduce the costs of the zener diodes.

(Zener Voltage)

Now, a range (a zener voltage range) of zener diodes suitable as thesecond zener diode 72 and the first zener diode 71 will be describedwith reference to FIG. 9. The zener voltage of a general zener diode isdefined as a range which is defined by a minimum value and a maximumvalue, not as a certain specific value. In the following description,the second zener diode 72 will be described as an example.

The maximum value of the zener voltage of the second zener diode 72 islower than the maximum operation guarantee voltage (for example, 6.45 V)of the charger 13. According to this configuration, it is possible toavoid voltage equal to or higher than the maximum operation guaranteevoltage from being input to the charger 13, and it is possible to stablyinput voltage lower than the maximum operation guarantee voltage.

The minimum value of the zener voltage of the second zener diode 72 ishigher than the minimum operation guarantee voltage (for example, 4.45V) of the charger 13. According to this configuration, is possible toavoid voltage lower than the minimum operation guarantee voltage frombeing input to the charger 13, and it is possible to stably inputvoltage equal to or higher than the minimum operation guarantee voltage.

A value which is obtained by subtracting the maximum value of the zenervoltage of the second zener diode 72 from the maximum operationguarantee voltage of the charger 13 is smaller than a value which isobtained by subtracting the minimum operation guarantee voltage of thecharger 13 from the minimum value of the zener voltage of the secondzener diode 72. According to this configuration, it is possible to lowerthe frequency at which the second zener diode 72 breaks down. Therefore,it is possible to suppress heat generation of the second zener diode 72,and it is possible to extend the life of the second zener diode 72.

Actually, the resistance values of general zener diodes and currentswhich flow through the zener diodes in the breakdown state are notsmall. Therefore, it is preferable that heat generation of zener diodesin the breakdown state should be suppressed. Also, in the case wherevoltage to be input to the charger 13 is lower than the maximumoperation guarantee voltage of the charger 13, stabilization of thevoltage by the zener diode is not essential.

The rated value of voltage which can be supplied from the chargingterminal 43 (for example, 5.0 V) is higher than the minimum operationguarantee voltage of the charger 13, and the minimum value of the zenervoltage of the second zener diode 72 is higher than the rated value ofvoltage which can be supplied from the charging terminal 43 (the ratedvoltage). According to this configuration, the second zener diode 72never breaks down. Therefore, it is possible to efficiently use thesecond zener diode 72 with respect to voltage which is supplied from thecharging terminal 43.

A value which is obtained by subtracting the maximum value of the zenervoltage of the second zener diode 72 from the maximum operationguarantee voltage of the charger 13 is smaller than a value which isobtained by the rated value of voltage which can be supplied from thecharging terminal 43 from the minimum value of the zener voltage of thesecond zener diode 72. According to this configuration, it is possibleto lower the frequency at which the second zener diode 72 breaks down.Therefore, it is possible to suppress heat generation of the secondzener diode 72, and it is possible to extend the life of the secondzener diode 72.

For each of components (Z1 to Z5 of FIG. 9) for zener diodes, a minimumvalue for zener voltage and a maximum value for zener voltage aredetermined. Therefore, a zener diode having the above-mentioned zenervoltage range is selected. Therefore, as the second zener diode 72 andthe first zener diode 71, the components Z2 to Z4 are preferable, andthe component Z2 is most preferable. In the second zener diode 72 andthe first zener diode 71, identical components may be used, or differentcomponents may be used.

In the above-described embodiment, in order to stabilize voltage to beinput to the charger 13, the second zener diode 72 is used. However, inorder to stabilize voltage to be input to the control unit 50, anotherzener diode may be used. Since the control unit 50 also has a maximumoperation guarantee voltage and a minimum operation guarantee voltagesimilarly to the charger 13, it is possible to use zener diodes havingappropriate zener voltage ranges based on them.

(Resistor)

The resistor 73 is provided between the first zener diode 71 and thesecond zener diode 72 so as to be connected in series with the firstzener diode 71 and the second zener diode 72. According to thisconfiguration, since voltage is dropped by the resistor 73, it ispossible to prevent high voltage from being input to the charger 13.Furthermore, since voltage equal to or higher than the zener voltage isunlikely to be applied to the first zener diode 71, it is possible tosuppress heat generation of the first zener diode 71.

The resistor 73 is connected on the upstream side from the conductivemember 78 in the flow direction of power which is input from thecharging terminal 43. Specifically, the resistor 73 is provided on thefirst circuit board 76 apart from the second circuit board 77 on whichthe charger 13 is provided. According to this configuration, it ispossible to separate the resistor 73 which is a heat generating elementfrom the charger 13.

(First Capacitor)

The first capacitor 74 is provided between the charging terminal 43 andthe charger 13 so as to be connected in parallel with the charger 13.According to this configuration, it is possible to make the firstcapacitor 74 function as a smoothing capacitor to stabilize voltage tobe input to the charger 13. Also, the first capacitor 74 is connected tothe conductor so as to be closer to the charger 13 than to the chargingterminal 43. Therefore, it is possible to further stabilize voltage tobe input to the charger 13.

Since the resistance component of the conductor electrically connectingthe charging terminal 43 and the charger 13 and the first capacitor 74constitute a low pass filter, it is possible to restrain high-frequencynoise from being input to the charger 13. Also, since the firstcapacitor 74 is provided between the first zener diode 71 and thecharger 13 so as to be connected in parallel with the charger 13, minorchanges in voltage which cannot be eliminated by the first zener diodeare smoothed by the first capacitor 74. Therefore, it is possible toinput stabler voltage to the charger 13. Also, in the case of using theabove-described resistor 73, the resistor 73 also constitutes a part ofthe low pass filter.

Therefore, as shown in FIG. 10, the smoothing capacitor smoothes ripplecomponents (pulsation components) included in input voltage Vin, usingthe charging action and discharging action of the capacitor, therebystabilizing output voltage Vout. Also, the low pass filter is a filterwhich is composed of a capacitor (C) and a resistance component (R), asshown in FIG. 11, and removes high-frequency noise, and passeslow-frequency noise. The cutoff frequency f of the low pass filter (themaximum frequency of frequencies which the low pass filter passes) isexpressed as the following formula.f=½πRC

In order to reduce the area on the circuit board which the firstcapacitor 74 occupies, it is preferable to reduce the capacity (size) ofthe first capacitor within such a range that the first capacitor caneliminate ripple components. However, if the capacity of the firstcapacitor 74 is reduced, the cutoff frequency becomes higher. Therefore,there is a possibility that the first cartridge cannot exhibitsufficient noise removal performance. For this reason, in the powersupply unit 10 of the present embodiment, while the capacity of thefirst capacitor 74 is set to be small, the resistance component is setto be large. As a result, the cutoff frequency is suppressed so as to below, and necessary noise removal performance is secured. Hereinafter,configurations for setting the resistance component to be large will belisted.

As described above, the first capacitor 74 is provided on the secondcircuit board 77, together with the charger 13. The second circuit board77 is apart from the first circuit board 76 on which the chargingterminal 43 is provided, and is electrically connected to the firstcircuit board 76 through the conductive member 78. In other words, onthe upstream side of the first capacitor 74, the conductive member 78exists, and the cutoff frequency becomes low due to the resistancecomponent of the conductive member 78. Therefore, it is possible toimprove noise removal performance.

As described above, the first circuit board 76 is provided on one endside of the power supply 12 in the longitudinal direction (or the widthdirection), and the second circuit board 77 is provided on the other endside of the power supply 12 in the longitudinal direction (or the widthdirection). In other words, the first circuit board 76 and the secondcircuit board 77 are provided on the opposite sides of the power supply12 in the longitudinal direction (or the width direction). Therefore, itis possible to secure the length of the conductive member 78. As aresult, it is possible to increase the resistance component of theconductive member 78, thereby lowering the cutoff frequency. In otherwords, it is possible to widen the frequency band of removable noise.

On the input side of the first capacitor 74, i.e. on the conductorbetween the first capacitor 74 and the charging terminal 43, theabove-mentioned resistor 73 is provided. The resistance component of theresistor 73 lowers the cutoff frequency. Therefore, it is possible toimprove noise removal performance. Also, since the resistor 73 dropsvoltage, it is possible to restrain high voltage from being input to thecharger 13. Also, since the resistor 73 is provided on the first circuitboard 76, it is possible to decrease the amount of heat generation ofthe second circuit board 77 on which the charger 13 and the control unit50 are provided.

According to the above-described configuration, the resistance componentis set to be large. Therefore, it is possible to suppress the cutofffrequency so as to be low, and secure necessary noise removalperformance.

The capacity of the first capacitor 74 can be set to 1 μF or less.According to this configuration, by selecting a capacitor havingsufficient capacity required for the power supply unit 10 for theaerosol inhaler, it is possible to avoid the size of the power supplyunit 10 from increasing.

Also, it is preferable that the capacity of the first capacitor 74should be 0.1 μF or less. According to this configuration, it ispossible to reduce the size of the power supply unit 10 while selectinga capacitor having sufficient capacity required for the power supplyunit 10 for the aerosol inhaler.

(Second Capacitor)

The second capacitor 75 is connected on the input side of the controlunit 50, in parallel with the control unit 50. According to thisconfiguration, by making the second capacitor 75 function as a smoothingcapacitor, it is possible to stabilize voltage to be input to thecontrol unit 50. Similarly to the first capacitor 74, the secondcapacitor 75 also is connected to the conductor so as to be closer tothe control unit 50 than to the charging terminal 43. Therefore, it ispossible to further stabilize voltage to be input to the control unit50.

The capacity of the second capacitor 75 is different from the capacityof the first capacitor 74. In other words, since objects (the charger 13and the control unit 50) which the first capacitor 74 and the secondcapacitor 75 should protect are different, by selecting capacitorshaving appropriate capacities according to the objects to be protected,it is possible to reduce the areas on the board which the capacitorsoccupy.

The maximum operation guarantee voltage of the charger 13 (for example,6.45 V) is higher than the maximum operation guarantee voltage of thecontrol unit 50 (for example, 5.5 V). For this reason, as the secondcapacitor 75, a capacitor having a capacity larger than that of thefirst capacitor 74 is selected. As described above, the capacity of thesecond capacitor 75 which is provided on the input side of the controlunit 50 having low withstand voltage performance is set to be largerthan the capacity of the first capacitor 74 which is provided on theinput side of the charger 13. Therefore, it is possible to more surelyprotect the control unit 50 inferior in withstand voltage performance.

The charger 13 is configured to be able to control charging of the powersupply 12, and operate only during charging of the power supply 12, andthe control unit 50 is configured to operate during charging of thepower supply 12 and during discharging of the power supply. Therefore,as the second capacitor 75, a capacitor having a capability larger thanthat of the first capacitor 74 is selected. As described above, thecapacity of the second capacitor 75 which is provided on the input sideof the control unit 50 which operations during charging of the powersupply 12 and during discharging is set to be larger than the capacityof the first capacitor 74 which is provided on the input side of thecharger 13 which operates only during charging. Therefore, it ispossible to more surely protect the important control unit 50 to befrequently used.

The control cycle (operation clock) of the charger 13 is longer than thecontrol cycle of the control unit 50. For this reason, as the secondcapacitor 75, a capacitor having a capacity larger than that of thefirst capacitor 74 is selected. As described above, the capacity of thesecond capacitor 75 which is provided on the input side of the controlunit 50 having the short control cycle is set to be larger than thecapacity of the first capacitor 74 which is provided on the input sideof the charger 13 having the long control cycle. Therefore, it ispossible to more surely protect the control unit 50 having highperformance.

The control unit 50 is electrically connected to the operation unit 14which the user can operate, and the inhalation sensor 15 for detectinginhaling actions of the user. For this reason, as the second capacitor75, a capacitor having a capacity larger than that of the firstcapacitor 74 is selected. According to this configuration, since thecapacity of the second capacitor 75 which is provided on the input sideof the control unit 50 which is electrically connected to the operationunit 14 and the inhalation sensor 15 is set to be larger than that ofthe first capacitor 74, it is possible to more surely protect thecontrol unit 50 likely to be influenced by electrostatic noise enteringthrough the operation unit 14 and the inhalation sensor 15.

On the input side of the first capacitor 74, the first zener diode 71 isprovided so as to be connected in parallel with the first capacitor 74.Therefore, even if the capacity of the first capacitor 74 is set to besmaller than the capacity of the second capacitor 75, it is possible toprotect the charger 13 by the voltage stabilization action of the firstzener diode 71.

It is preferable that the capacity of the second capacitor 75 should be10 times to 100 times the capacity of the first capacitor 74. Forexample, the capacity of the first capacitor 74 is set to 0.1 μF, andthe capacity of the second capacitor 75 is set to 10 μF. As describedabove, capacitors having appropriate capacities according to objects tobe protected are mounted. Therefore, it is possible to reduce the areason the board which the capacitors occupy while protecting the objects.

(Layout on Second Circuit Board)

As shown in FIG. 3 and FIG. 5, the operation unit 14 and the inhalationsensor 15 are provided on the second circuit board 77. Electrostaticnoise such as static electricity entering through the operation unit 14and the inhalation sensor 15 is smoothed by the capacitors 74 and 75which are provided on the second circuit board 77.

The second circuit board 77 has a first main surface 77 a, and a secondmain surface 77 b which is the back of the first main surface 77 a, andthe operation unit 14 is provided on the first main surface 77 a, andthe inhalation sensor 15 is provided on the second main surface 77 b. Asdescribed above, the operation unit 14 and the inhalation sensor 15 areprovided on the different surfaces of the second circuit board 77.Therefore, it is possible to restrain electrostatic noise enteringthrough the operation unit 14 and electrostatic noise entering throughthe inhalation sensor 15 from being superimposed to form large noise.

The capacitors 74 and 75 are provided on the second main surface 77 b ofthe second circuit board 77. In other words, the second main surface 77b is a circuit mounting surface. As described above, the capacitors 74and 75 and the operation unit 14 are provided on the different surfacesof the second circuit board 77. Therefore, it is possible to secure aspace for the capacitors 74 and 75 to be disposed.

The operation unit 14 is required to be exposed from the surface of thepower supply unit 10 because of its role, so it is likely to become anelectrostatic noise entry route.

Electrostatic noise is received by the first main surface 77 a, notdirectly by the second main surface 77 b on which the capacitors 74 and75 are provided. Therefore, it is possible to restrain electrostaticnoise from reaching the second main surface 77 b. Therefore, capacitorshaving large capacities are unnecessary. Therefore, it is possible toreduce the areas on the board which capacitors occupy.

However, the present invention is not limited to the above-describedembodiment, and modifications, improvements, etc. can be made properly.

In this specification, at least the following inventions (1) to (8) aredisclosed. Moreover, although the corresponding constituent elements andthe like in the embodiments described above are shown in parentheses, itis not limited thereto.

(1) A power supply unit (the power supply unit 10) for an aerosolinhaler (the aerosol inhaler 1), the power supply unit comprising:

-   -   a power supply (the power supply 12) able to discharge power to        a load (the load 21) for generating an aerosol from an aerosol        source (the aerosol source 22);    -   a first control device (the charger 13) and a second control        device (the control unit 50) which are configured to control at        least one of charging and discharging of the power supply;    -   a circuit board (the second circuit board 77) on which the first        control device and the second control device are provided;    -   a first capacitor (the first capacitor 74) which is provided on        an input side of the first control device so as to be connected        in parallel with the first control device; and    -   a second capacitor (the second capacitor 75) which is provided        on an input side of the second control device so as to be        connected in parallel with the second control device,    -   wherein a capacity of the first capacitor is different from a        capacity of the second capacitor.

According to (1), since the capacity of the first capacitor which isprovided on the input side of the first control device so as to beconnected in parallel with the first control device and the capacity ofthe second capacitor which is provided on the input side of the secondcontrol device so as to be connected in parallel with the second controldevice are set to be different, it is possible to mount capacitorshaving appropriate capacities according to the control devices requiredto be protected, and it is possible to reduce the areas on the boardwhich the capacitors occupy.

(2) The power supply unit according to (1), wherein

-   -   a maximum operation guarantee voltage of the first control        device is higher than a maximum operation guarantee voltage of        the second control device, and    -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor.

According to (2), since the capacity of the first capacitor which isprovided on the input side of the first control device is set to besmaller than the capacity of the second capacitor which is provided onthe input side of the second control device having low withstand voltageperformance, it is possible to more surely protect the control deviceinferior in withstand voltage performance.

(3) The power supply unit according to (1), wherein

-   -   the first control device is configured to be able to control the        charging of the power supply and operate only during the        charging of the power supply,    -   the second control device is configured to operate during the        charging of the power supply and during the discharging of the        power supply, and    -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor.

According to (3), since the capacity of the first capacitor which isprovided on the input side of the first control device configured tooperate only during the charging is set to be smaller than the capacityof the second capacitor which is provided on the input side of thesecond control device configured to operate during the charging of thepower supply and during the discharging of the power supply, it ispossible to more surely protect the important control device to befrequently used.

(4) The power supply unit according to (1), wherein

-   -   a control cycle of the first control device is longer than a        control cycle of the second control device, and    -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor.

According to (4), since the capacity of the first capacitor which isprovided on the input side of the first control device having a longcontrol cycle is set to be smaller than the capacity of the secondcapacitor which is provided on the input side of the second controldevice having a short control cycle, it is possible to more surelyprotect the control device having high performance.

(5) The power supply unit according to any one of (1) to (4), wherein

-   -   the first control device is a charger (the charger 13) which is        configured to convert power, which is input, into charging power        for the power supply,    -   the second control device is a microcontroller (the control unit        50) which is configured to be able to control the charging and        the discharging of the power supply, and    -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor.

According to (5), since the capacity of the first capacitor which isprovided on the input side of the charger is set to be smaller than thecapacity of the second capacitor which is provided on the input side ofthe microcontroller, it is possible to more surely protect themicrocontroller which is a control device more important than thecharger.

(6) The power supply unit according to any one of (1) to (5), wherein

-   -   the power supply unit further includes at least one of a switch        (the operation unit 14) which a user can operate and a sensor        (the inhalation sensor 15) configured to output an inhaling        action of a user,    -   the switch or the sensor is electrically connected to the second        control device, and    -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor.

According to (6), since the capacity of the first capacitor is set to besmaller than the capacity of the second capacitor which is provided onthe input side of the second control device to which the switch or thesensor is electrically connected, it is possible to more surely protectthe control device likely to be influenced by electrostatic noiseentering through the switch and the sensor.

(7) The power supply unit according to any one of (1) to (6), wherein

-   -   the capacity of the first capacitor is smaller than the capacity        of the second capacitor, and    -   the power supply unit further includes a zener diode (the first        zener diode 71) which is provided on an input side of the first        capacitor so as to be connected in parallel with the first        capacitor.

According to (7), since the zener diode also is used on the input sideof the first control device where the first capacitor having a smallcapacity is provided, it is possible to more surely protect the controldevice, as compared to the control device which is protected by thecapacitor having the small capacity.

(8) The power supply unit according to any one of (1) to (7), wherein

-   -   the capacity of the second capacitor is 10 times to 100 times        the capacity of the first capacitor.

According to (8), by mounting capacitors having appropriate capacitiesaccording to the control devices required to be protected, it ispossible to reduce the areas on the board which capacitors occupy.

According to an aspect of the present invention, it is possible toreduce the areas on the circuit board which the capacitors occupy whileappropriately protecting the plurality of control devices.

What is claimed is:
 1. A power supply unit for an aerosol inhaler, thepower supply unit comprising: a power supply able to discharge power toa load for generating an aerosol from an aerosol source; a charger whichis configured to convert power, which is input, into charging power forthe power supply; a microcontroller which is configured to be able tocontrol charging and discharging of the power supply; a circuit board onwhich the charger and the microcontroller are provided; a firstcapacitor which is provided on an input side of the charger so as to beconnected in parallel with the charger; and a second capacitor which isprovided on an input side of the microcontroller so as to be connectedin parallel with the microcontroller, wherein a capacity of the firstcapacitor is smaller than a capacity of the second capacitor, thecharger is configured to be able to control the charging of the powersupply and operate only during the charging of the power supply, themicrocontroller is configured to operate during the charging of thepower supply and during the discharging of the power supply, and acontrol cycle of the charger is longer than a control cycle of themicrocontroller.
 2. The power supply unit according to claim 1, whereina maximum operation guarantee voltage of the charger is higher than amaximum operation guarantee voltage of the microcontroller.
 3. The powersupply unit according to claim 1, wherein the power supply unit furtherincludes at least one of a switch which a user can operate and a sensorconfigured to output an inhaling action of a user, and the switch or thesensor is electrically connected to the microcontroller.
 4. The powersupply unit according to claim 1, wherein the power supply unit furtherincludes a zener diode which is provided on an input side of the firstcapacitor so as to be connected in parallel with the first capacitor. 5.The power supply unit according to claim 1, wherein the capacity of thesecond capacitor is 10 times to 100 times the capacity of the firstcapacitor.
 6. The power supply unit according to claim 1, wherein thecircuit board has two main surfaces, and the first capacitor and thesecond capacitor are provided on one of the main surfaces.
 7. The powersupply unit according to claim 1, wherein the power supply unit includesan operation unit which a user can operate, the circuit board has afirst main surface and a second main surface, the first capacitor andthe second capacitor are provided on the second main surface, and theoperation unit is provided on the first main surface.